2003 HONDA CIVIC Ignition switch

EPS Gomponents
7.
8.
DTC Troubleshooting (cont'dl
Turn the ignition switch OFF, and disconnect EPS
control unit connector C (20P).
Start the engine, and let it idle.
Measure the voltage between EPS control unit
connector C {20P) terminal No.19 and body ground.
EPS CONTROL UNIT CONNECTOR C {2OP)
ls there about 6 V at idle? (With the meter set lol
t requency, is there 33 Hz per 1,000 engine rpm? )
YES Check for loose EPS control unit connectors.
lf necessary, substitute a known-good EPS control
unit and recheck.l
NO Repair open in the wire between the EPS
control unit and the ECM.I
Turn the ignition switch OFF, and disconnect EPS
control unit connector C (20P).
Start the engine, and let it idle.
9.
10.
Wire side of {emale terminals
17-34
11. Measure the voltage between EPS control unit
connector C (20P)terminal No. 19 and body ground.
EPS CONTROL UNIT CONNECTOR C {2OPI
Wire side of female terminals
ls there about 6 V at idle? (With the metet set tor
trequency, is therc 33 Hz per 1,000 engine rpn?)
YES Check for loose EPS control unitconnectors.
lf necessary, substitute a known-good EPS control
unit and recheck.I
NO Go to step '12.
Turn the ignition switch OFF.
Disconnect the ECM connector E (31P) connector.
12.
13.
!

EPS Components
DTC Troubleshooting (cont'dl
DTC 41: Voltage For Motor
1. Clear the DTC.
2. Start the engine.
3. Turn the steering wheel from lock-to-lock several
times, and wait 10 seconds or more,
Does the EPS indicator come on?
YES-Go to step 4.
NO Check for loose wires or poor connections. lf
the connections are good, the system is OK at this
time.l
4. Stop the engine, and verify the DTC.
ls DTC 41 indicated?
YES Go to step 5.
NO Perform the appropriate troubleshooting for
the code indicated.l
5. Make sure the ignition switch is OFF, then
disconnect EPS control unit connector B (2P) and
the motor 2P conneclor.
6. Check for continuity between EPS control unit
connector B (2P) terminal No. 1 and body ground.
EPS CONTROL UNIT CONNECTOR B {2P}
M1 (RED} HF---t||
Itr(f))
T,L
Wire side of female terminals
ls there continuity?
YES Repair short to body ground in the RED wire
between the EPS control unit and the motor. !
NO-Go to step 7.
17-36
7. Check for continuity between EPS control unit
connector B (2P)terminal No. 2 and body ground.
EPS CONTROL UNIT CONNECTOR B I2P)
TitM2 {GRN) FJ
-r
o)
TI
Wire side of female terminals
ls there continuity?
YES-Repair short to body ground in the GRN wire
between the EPS control unit and the motor,l
NO Go to step 8.
Check for continuity between EPS control unit
connector B (2P)terminal No. 1 and No. 2.
EPS CONTROL UNIT CONNECTOR B {2P)
Wire side of female terminals
ls there continuity?
YES Repair short between the RED and GRN
wires in the motor circuit between the EPS control
unit and the motor.l
NO Go to step 9.
M2 (GRNI
.l
\

9. Turn the ignition switch ON (ll), and measure the
voltage between EPS control unit connector B (2P)
terminal No. 1 and body ground
EPS CONTROL UNIT CONNECTOR B (2P)
M1 IREDI Hr-_ -1 ||
tr,<.)\uL,/Y
I
Wire side oI female terminals
Is there battety voltage?
YES Repair short to power in the + circuit wire
between the EPS control unit and the motor.I
NO-Go to step 10.
Measure the voltage between EPS control unit
connector B (2P)terminal No.2 and body ground.
EPS CONTROL UNIT CONNECTOR B (2P)
10.
raz rcnrrrr l{l-t . I
I(v)
YI
Wire side of female terminals
ls there battery voltage?
YES-Repair shortto power in the - circuitwire
between the EPS control unit and the motor.!
NO Go to step 11.
11.Turn the ignition switch is OFF.
Substitute a known-good EPS control unit, and
connect all the disconnected connectors.
Start the engine, and turn the steering wheel from
lock to lock several times.
Does the EPS indicator come on?
YES-Go to step 14.
NO-Check for loose or poor connections atthe
EPS control unit and the motor connections. lfthe
connections are good, replace the EPS control unit
and recheck.l
Stop the engine, and verity the DTC.
ls DTC 41 ind icated?
YES Replace the steering gearbox motor and
recheck.l
NO Perform the appropriate troubleshooting for
the code indicated.l
13.
14.
17-37

EPS Components
{DTC Troubleshooting (cont'd)
DTC 42,45: Motor Driven Current
1. Clear the DTC.
2. Sta rt the engine.
3. Turn the steering wheel from lock-to-lock several
times, and wait 10 seconds or more.
Does the EPS indicator come on?
YES- Go to step 4.
NO-Check for loose wires or poor connections. lf
the connections are good, the system is OK at this
time.I
Stop the engine, and verify the DTC.
ls DTC 42 or 45 indicated?
YES-Go to step 5.
NO- Perform the appropriate troubleshooting for
the code indicated.I
Make sure the ignition switch is OFF, then
disconnect EPS control unit B connector (2P) and
the motor 2P connector.
Check for continuity between EPS control unit
connector B (2P)terminal No. 1 and body ground.
EPS CONTROL UNIT CONNECTOR B I2P)
M1 IRED} H
I f2-l
(C))
TI
Wire side of female terminals
ls there continuity?
YES Repair short to body ground in the RED wire
between the EPS control unit and the motor,I
NO-Go to step 7.
6.
17-38
7. Check for continuity between EPS control unit
connector B (2Plterminal No.2 and body ground.
EPS CONTROL UNIT CONNECTOR B I2PI
r',rz tcnnrt ll
-]-(o)
TI
Wire side of female terminals
lsthere continuity?
YES Repair short to body ground in the GRN wire
between the EPS control unit and the motor.l
NO Go to step 8.
Check for continuity between EPS control unit
connector B (2P) terminal No. 1 and No. 2.
EPS CONTROL UNIT CONNECTOR B {2P)
Wire side of female terminals
ls there continuity?
YES Repair short between the RED and GRN
wires in the motor circuit between the EPS control
unit and the motor.l
NO Go to step 9.
M2 {GRN)

9. Turn the ignition switch ON (ll), and measure the
voltage between EPS control unit connector B (2P)
terminal No. I and body ground.
EPS CONTROL UNIT CONNECTOR B (2PI
M1 {RED} HT-----l | |lil
(v)
I
I
Wire side o{ Iemale terminals
ls there battety voltage?
YES-Repair short to power in the + circuit wire
between the EPS control unit and motor.l
NO Go to step 10.
Measure the voltage between EPS control unit
connector B {2P}terminal No. 2 and body ground.
EPS CONTROL UNIT CONNECTOR B (2P}
mz rcnrur ll-l
A(v)
YI
Wire side of female terminals
ls there battery voltage?
YES Repair short to power in the + circuitwire
between the EPS control unit and the motor.a
NO- Go to step 1 1.
10.
11. Check for continuity between EPS control unit
connector B (2P) terminal No. 1 and the motor 2P
connector terminal No. 2.
EPS CONTROL UNITCONNECTOR B 12P)MOTOR CONNECTOR {2PI
M1 IRED)
M1 (RED}
Wire side of female terminals
ls there continuity?
YES-Go to step '12.
NO-Repair open in the RED wire between the EPS
control unit and the motor.l
(cont'd)
17-39

DTC tli|: Motor Driven Current is Excessively
Hish
1. Clear the DTC.
2. Start the engine.
3. Turn the steering wheel from lock-to-lock several
times, and wait '10 seconds or more.
Does the EPS indicator come on?
YES Go to step 4.
NO-Check for loose wires or poor connections. lf
the connections are good, the system is OK at this
ttme.I
4. Stop the engine, and verify the DTC.
ls DTC 43 indicated?
YES Go to step 5.
NO-Perform the appropriate troubleshooting for
the code indicated.I
5. Make sure the ignition switch is OFF, then
disconnect EPS control unit connector B (2P) and
the motor 2P connector.
6. Turn the ignition switch ON (ll).
7. Measure the voltage between EPS control unit
connector B (2P)terminal No. '1 and body ground.
EPS CONTROL UNIT CONNECTOR B {2P}
M1 {REo) HT------t I I
Itr(v)
T-L
Wire side ot Iemale terminals
ls therc battery voltage?
YES Repair short to power in the + circuit wire
between EPS control unit and motor.l
NO-Go to step 8.
8. Measure the voltage between EPS control unit
connector B (2P)terminal No. 2 and body ground.
EPS CONTROL UNIT CONNECTOR B I2PI
TilM2 tcRNl F-lf---1 z I
(v)
Y
I
Wire side of female terminals
ls there battety voltage?
YES- Repair short to power in the - circuit wire
between the EPS contorl unit and the motor. !
NO-Go to step 9.
Turn the ignition switch OFF.
Check for continuity between EPS control unit
connector B (2P) terminals No. 1 and No. 2.
EPS CONTROL UNIT CONNECTOR B {2P)
Wire side of female terminals
ls there continuity?
YES Repair short between the GRN and RED
wires in the motor circuit between the EPS control
unit and the motor.l
NO Gotostep 11.
9.
10.
(cont d)
17-41
M2 {GBN)

EPS Indicator Circuit Troubleshooting
1.Turn the ignition switch ON (ll), start the engine,
and watch the EPS indicator.
Does the EPS indicator come on?
YES lf the EPS indicator comes on and goes off, it's
OK. lf the EPS indicator stays on or blinks. go to
step 12.
NO Go to step 2.
Turn the ignition switch OFF, then ON (ll) again,
and watch the brake system indicator,
Does the brake system indicator come on?
YES-Go to step 3.
NO Repair open in the indicator power source
circuit.l. Blown No. 10 (7.5A)fuse.
. Open in the wire between the No. 10 (7.5A) fuse
and gauge assembly.. Open circuit inside the under-dash fuse/relay box,. Faulty gauge assembly.
Turn the ignition switch OFF,
Connect a jumper wire between the gauge
assembly 22P connector terminal No. 13 and body
ground, then turn the ignition switch ON (ll).
GAUGE ASSEMBLY 22P CONNECTOR (Blue connector)
Wire side of female terminals
Does the EPS indicator come on?
YES-Go to step 5.
NO Inspect the EPS indicator bulb, if the bulb is
OK, replace the bulb circuit board in the gauge
assembly.l
3.
4.
5. Turn the ignition switch OFF.
6. Disconnect EPS control u n it connector C (20P).
7. Turn the ignition switch ON (ll).
8. Connect EPS control unit connector C (20P)
terminal No. 6 to body ground with a jumper wire.
Wire s d€ oflemale16rmina s
Does the EPS indicatot come on?
YES Go to step 9.
NO Repair open in the wire between the gauge
assembly and the EPS control unit.l
Turn the ignition switch OFF.
Disconnect EPS control unit connector A (2P),
Check for continuity between EPS control unit
connector A terminal No. 2 and body ground.
EPS CONTROL UNITCONNECTOA A I2PI
wire s de oftemale terminals
ls there continuity?
YES Check for loose or poor connections at the
EPS control unit. lf the connections are good,
substitute a known-good EPS control unit. lf the
symptom/indication goes away, replace the
original EPS control unit and recheck.I
NO Repair open in the wire or a bad ground at
G151,t(cont'd)
9.
10.
'l 1.
EPS CONTBOL UNIT CONNECTOB C {2OP)
17-47

EPS Components
I
12.
EPS Indicator Circuit Troubleshooting (cont'dl
Turn the ignition switch OFF.
Disconnect EPS control unit connector C (20P).
Turn the ignition switch ON (ll).
Does the EPS indicator come on?
YES-Repair short to ground in the YEUBLU wire
between the gauge assembly and the EPS control
unit, or replace the bulb circuit board in the gauge
assembly.l
NO-Go to step 15.
Measure the voltage between EPS control unit
connector C (20P)terminal No. 10 and body ground.
EPS CONTROL UNIT CONNECTOR C I2OP)
Wire side of female terminals
ls there battery voltage?
YES-Go to step 16.
NO-Repair open in the wire between EPS control
unit connector C (20P) and the No, 10 (7.5A) fuse. t
13.
14.
17-48
16. Measure the voltage between EPS control unit
connector A (2P)terminal No. '1 and body ground.
EPS CONTROL UNITCONNECTON A (2P}
+B (WHT/BLUI H
Itr
v-L
17.
18,
19.
20.
Wire side of female terminals
ls there battery voltage?
YES-Go to step 17.
NO-Check for a blown No. 18 (604) fuse in the
under-hood fuse/relay box or open/short in the
WHT/BLU wire between the under-hood fuse/relay
box and the EPS control unit.l
Turn the ignition switch OFF.
Reconnect EPS control unit connector A (2P).
Turn the ignition switch ON (ll).
Measure the voltage between EPS control unit
connector C (20P)terminal No. 8 and body ground.
EPS CONTROL UNIT CONNECTOR C (2OP)
Wire side of female terminals
ls therc about 10 V?
YES Check for loose or poor connections at the
EPS control unit. lf the connections are good,
substitute a known-good EPS control unit. lf the
symptom/indication goes away, replace the
original EPS control unit and recheck.l
NO Repair short to ground in the BRN wire
between the data link connector and the EPS
control unit.I